OpenLCP/protocols/sacn/README.md

# Library for E1.31 sACN
## `Lightweight streaming protocol for transport of DMX512 using ACN`

## Top level include

Include `sacn.h` for full protocol support.

> ```#include "sacn.h"```

### Requirements
Expects to also have the `acn` and `dmx` libraries in the include path.

## Logical components

### Protocol Handling
* `sacn.h`: [`SACN`] protocol constants.
* `data.h`: [`SACN::DATA`] protocol support for `VECTOR_ROOT_E131_DATA` packets.
* `extended.h`: [`SACN::EXTENDED`] protocol support for `VECTOR_ROOT_E131_EXTENDED` packets

### Data Classes
* `universe.h`: [`SACN::Universe`]  A set of up to 512 data slots identified by universe number. Note: In E1.31 there may be multiple sources for a universe.
> For protocol agnostic universe refer to the base class, `DMX::Universe`

* `receiver.h`: [`SACN::Receiver`] A receiver is the intended target of information from a source. A receiver may listen for multiple universes.

* `source.h`: [`SACN::Source`] A sACN component that assembles, formats, and transmits data to one or many receivers.

* `node.h`: [`SACN::Node`] A class that inherits from both `SACN::Source` and `SACN::Receiver`.  IE. can both send and receive.  The node class also manages universe discovery.

### Reference Implementations

Several reference implementations may be available in the `platform` subdirectory.

* `receiver-esp.h`: [`SACN::EspReceiver`] A reference implementation, derived from `SACN::Receiver` for use with ESP devices and Arduino.

* `qsacnnode.h`: [`SACN::QSacnNode`] An implementation that inherits from `SACN::Node`, which handles all of the mucky hardware and network with Qt.

## Usage with Arduino

Include `receiver-esp.h` at the top of your sketch.

Create a receiver object.
> ```
> EspReceiver * e131 = new EspReceiver();
> ```

In `setup`, subscribe to a universe an register a callback for data activity.
> ```
setup() {
  e131->subscribe(1);
  e131->universe(1)->onData(std::bind(&universeHandler,
                                      std::placeholders::_1));
}
>```

Write a handler function with the follow signature (returns `void`, requires 1 argument, a `Universe` pointer):
> ```
void universeHandler(Universe * universe) {
  do something...
}
> ```